Using Frequency Domain Reflectometry for Rapidly Measurement of Peanut Moisture Content = Using Frequency Domain Reflectometry for Rapidly Measurement of Peanut Moisture Content

다국어 초록 (Multilingual Abstract)

In order to achieve rapidly measurement of peanut moisture content, the Frequency Domain Reflectometry (FDR) system was designed and develop by combining a dual-probe frequency domain reflectometer and Latte Panda. For the peanut moisture content FDR measurement, the calibration curve is necessary to define at first. The peanut samples (Tainan No.9 and Tainan No.18) are separate into pods and kernels and pulverized into granule shape for the measurement. The samples are baked in the oven at 130°C for 6 hours for removing the water content and defined it as 0% moisture content. Then the different weights of water have been added into samples for making different moisture content peanuts. The different dielectric constant measured by FDR sensor system is corresponded as the different moisture content. The calibration curve can be obtained from the relationship between the different moisture content peanut samples and the corresponding dielectric constant. During the FDR measurement, 32 N/㎡ applying force to the sample is necessary for eliminating the air gap. Furthermore, different methods for measuring the peanut moisture content were carried out in the factory with the drying machine. The comparison and results of different measure methods during the drying process at factory has been completed. The result shows that different measuring method have the same peanut moisture content trend. In addition, another method for obtaining the calibration curve was carried out in this work. The peanuts were baked to different moisture content and measured the corresponding dielectric constant. The calibration curves of peanut’s pods and kernels and the accuracy test has been defined. The both correlation coefficients of the testing samples are more than 0.97. It proves that this proposal FDR system have high accuracy and is enable to rapidly measure from 5% to 60% moisture content of peanut.